Earnings Per Share - Computation Of Basic And Diluted Earnings Per Common Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	6 Months Ended
Jul. 31, 2016	Jul. 26, 2015	Jul. 31, 2016	Jul. 26, 2015
Earnings Per Share [Abstract]
Net income (loss)	$ 8,978	$ (313)	$ 15,866	$ (455)
Weighted average common shares outstanding - basic	65,299	65,920	65,222	66,319
Dilutive effect of options and restricted stock units	606	0	501	0
Weighted average common shares outstanding - diluted	65,905	65,920	65,723	66,319
Basic earnings (loss) per common share (in dollars per share)	$ 0.14	$ 0.00	$ 0.24	$ (0.01)
Diluted earnings (loss) per common share (in dollars per share)	$ 0.14	$ 0.00	$ 0.24	$ (0.01)
Anti-dilutive shares not included in the above calculations	1,466	2,894	1,774	2,418

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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